Question

tell me why we have found water on Mars but finding life still won't be easy. Why so

Answer 1

Because in Mars, the temperature is more, so evaporation occurs easily and in winter it drops to very low climate, human can't afford it

Answer 2

NASA's announcement that liquid water flowers on the surface of Mars has reignited enthusiasm over the possibility of alien planet on our planetary neighbour.Liquid water is essential for life to exist on earth , and knowing that H2O is flowing on the red planet strengthens the odds that extraterrestrial life exist somewhere on Mars as well.

Any alien life lurking on Mars will most likely be in the form of tiny microorganisms— not complex biological beings like the ones on our planet. That means finding these aliens is going to be tricky; they will probably be quite small and simple, hiding inside soil samples or hard to reach places.

To confirm the existence of such creatures, NASA and other research institutions are developing numerous technologies to search for biosignatures on Mars. A biosignature is any substance with a biologic origin — whether that be a one-million-year-old fossil or a living microbe.

Hey hope it helps you.